/proc/sys/vm/drop_caches
To free pagecache: echo 1 > /proc/sys/vm/drop_caches To free dentries and inodes: echo 2 > /proc/sys/vm/drop_caches To free pagecache, dentries and inodes: echo 3 > /proc/sys/vm/drop_caches linux 2.6.16 之後才有 refernece : http://people.arsc.edu/~kcarlson/software/man/drop_caches.html http://www.linuxidc.com/Linux/2010-03/24939.htm